Agents of Bioterrorism Flashcards Preview

Virology, Parasitology, Mycology > Agents of Bioterrorism > Flashcards

Flashcards in Agents of Bioterrorism Deck (33):

What are the categories of bioterrorism agents and a general description of the catergory?

Category A- easily disseminated, transmitted person-person, high mortality, potential major public health impact, panic or social disruption, special prep; B- 2nd highest, moderate morbidity, low mortality, moderate dissemination; C- 3rd, emerging pathogens that could be engineered for mass dissemination


What are the normal epidemiologic features of anthrax?

resevior- herbivores (goats, sheep, cattle), wollsortter's disease, soil- cell poor survival, spores (decades)


What are the virulence factors of anthrax?

antiphagocytic capsule- poly D glutamic acid, plasmid encoded (pX02), endotoxins- PA- protective Ag (binding site non-toxic), EF- edema factor (andenylate cyclase), lethal factor (protease), plasmid encoded (pX01); non-encapsulated is not virulent, 1 plasmid for capsule and 1 for toxin


Describe the mechanism of anthrax.

PA binds cell receptor, 7 PAs bound to receptor form a big compound and will bind 3 of either EF or LF (any combo), endocytosis, acidification of endosome by host cell casues secretion of EF/LF, EF- inc cAMP causing inhibition of phagocytosis and edema, LF- dec. MAPK-> apoptosis and cytokine production, necrosis and hypoxia


What are the types of anthrax? Which method is bioterrorism delivery?

cutaneous, GI, and inhalation (pulmonary, bioterrorism)


what are the features of cutaneous anthrax? GI?

most common (esp developing countries), septicemia rare, mortality <1%; extremely rare (none in US)


What are the features of inhalation (Pulmonary) anthrax?

spore germinate in lungs, not communicable, onset flu-like- SOB, sweats, fever/chills, fatigue, non-prod. cough, N/V, chest/muscle pain, headache; mediastinal widening on CXR, septicemic spread, rapid onset death 3-7d, resp fail, shock, meningitis, untreated 100% fatal


How is anthrax diagnosed?

blood/CSF culture- medusa head colonies, phenotypical or biochemical characteristics, PCR (RT-PCR), ELISA, or DFA; purple on outside, capsule doesn't stain


What us the therapy for anthrax?

ciprofloxacin or tetracycline; unless genetically selected against, then good chance gram + antibiotic will work


Who gets an anthrax vaccine?

military, lab workers; new recombinant vaccine under way, current vaccine poor


what are the general features of Yersinia pestis?

plague, enterobacter., "safety pin" bipolar staining, single most significant disease in W. civilization, killed 1/3 pop, "Black death"


what is the epidemiology of Y pestis in US? Sylvatic plague? Urban plague?

SW, fleas feeding on squirrels, prairie dogs, chipmunks, etc; S- flea to rodent to flea to rodent, humans get close to sick rodent and flea hops to human; U- rodent (wild) to flea to rodent (urban-rat) then flea to human; Y pestis grows in flea, regurgitated into host with next blood meal


What are the virulence factors of Y. Pestis?

many!!! big component of disease is the cytokine storm


What is the presentation, signs and symptoms of bubonic plague?

1-7d incubation after flea bite, fever, chills, headache, exhaustion, spreads to lymph nodes (unilateral), develop bubo (enlarged tender lymph node) esp groin, neck and armpit, skin hemorrhages- capillaries = black death, shock, death, mortality 8% treated >50% untreated, no person to person


How is pneumonic plague transmitted?

flea to rodent cycle, flea to human-> bubonic-> systemic spread to lungs (few patients), then aerolosized in lungs and spread out (person to person)


What is the presentation, signs and symptoms of bubonic plague? (bioterrorism)

1-4d incubation after inhalation (1-10 org), flu-like symp. w/ high fever, cough/bloody sputum, shock, death, mortality ~100% untreated and ~15% treated, person to person transmission


What is the drug of choice for confirmed plague?

streptomycin (difficult to get but other similar options exist)


How is plague prevented?

no vaccine, sylvatic/urban: bug repellant, pre-exposure prophylaxis AB, pneumonic- droplet precautions


What are the general features of Franciscella tularensis?

zoonotic gram (-) coccobacillus, obligate aerobe, facultative intracellular w/ macrophage (other ~10), causes rabbit fever, reservoir- rabbits, sheep, squirrels, deer etc, can be in food/water contaminated, or aerosol- bioterrorism


What are the tularemia types?

ulceroglandular (most common), glandular, occuloglandular, oropharyngeal and GI, pneumonic, and typhoidal


What are the signs and symptoms with ulceroglandular Tularemia?

skin (scratch or abrasion) or insect/tick bite, ulcer at site of infection, swollen painful lymph glands, fever, chills, headache, exhaustion


What are the signs and symptoms with glandular Tularemia?

swollen painful lymph glands, fever, chills, headache, exhaustion


What are the signs and symptoms with oculoglandular Tularemia?

eye pain/ redness/ swelling/ discharge, ulcer inside eyelid


What are the signs and symptoms with oropharyngeal Tularemia?

digestive tract, fever, pharyngitis, mouth ulcers, vomiting, diarrhea


What are the signs and symptoms with pneumonic Tularemia?

inhalation; cough, chest pain, difficulty breathing, respiratory failure, death, most likely bioterror mode, 30-60% fatal if untreated- respiratory failure


What are the signs and symptoms with typhoidal Tularemia?

consequence of any primary exposure leading to septicemia, high fever, extreme exhaustion, vomiting diarrhea, splenomegaly, hepatomegaly, and pneumonia


How is tularemia diagnosed?

workup in BSC, presumptive ID: gram stain, slow growing colonies on CHOC and none on BAP, oxidase and urease (-), weak catalase (+), confirmation PCR at Lab response network, reportable agent, document destruction of isolate


How is tularemia treated? prevented?

DOC: gentamicin (streptomycin), fatal if not treated 30-60%; vaccine- investigational but available w/ informed consent


what are the virulent features of Clostridium Botulinum Toxin?

most lethal substance known, aerosolized- 200g could kill entire US, neurotoxin- prevent ACh release, muscle contraction both voluntary and diaphragm


What is the presentation, signs, and symptoms of botulism?

onset 12-36hrs, early- dry mouth, blurred/double vision, late- symmetric descending weakness, diplopia, dysphagia, dysphonia, respiratory paralysis, death


What mechanisms can be employed for botulinum toxin in bioterrorism?

food/water, aerosol- inhalation= 100x more potent


How infectious is Burkholderia mallei? Routes and symptoms with each?

Glanders-Low infectious dose
Symptoms: Cutaneous-multiple abscesses; Eye, nose, other mucous membranes-mucopurulent discharge; Pulmonary/systemic-fever, myalgia, headache, chest pain, diarrhea


What does Burkeholderia pseudomallei cause?

Melioidosis (glanders-like)